from fastapi import Request, HTTPException
from collections import defaultdict
import time

# Einfaches In-Memory Rate Limiting
request_counts: dict = defaultdict(list)

RATE_LIMITS = {
    "search": (100, 60),   # 100 Requests pro 60 Sekunden
    "upsert": (50,  60),
    "embed":  (200, 60),
    "rag":    (20,  60),
}

def check_rate_limit(user_id: str, action: str):
    limit, window = RATE_LIMITS.get(action, (100, 60))
    now           = time.time()
    key           = f"{user_id}:{action}"

    # Alte Requests entfernen
    request_counts[key] = [
        t for t in request_counts[key]
        if now - t < window
    ]

    if len(request_counts[key]) >= limit:
        raise HTTPException(429, {
            "error": {
                "message": f"Rate limit erreicht: {limit} Requests pro {window}s",
                "type":    "rate_limit_error",
                "code":    "rate_limit_exceeded"
            }
        })

    request_counts[key].append(now)